Add a multi-threaded rendering example.

examples/ui/noodles/rasterizer.h

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef EXAMPLES_UI_NOODLES_RASTERIZER_H_
+#define EXAMPLES_UI_NOODLES_RASTERIZER_H_
+
+#include <memory>
+
+#include "mojo/gpu/gl_context.h"
+#include "mojo/gpu/gl_context_owner.h"
+#include "mojo/public/interfaces/application/application_connector.mojom.h"
+#include "mojo/services/gfx/composition/interfaces/scenes.mojom.h"
+#include "mojo/skia/ganesh_context.h"
+#include "mojo/ui/ganesh_renderer.h"
+
+namespace examples {
+
+class Frame;
+
+// Ganesh-based rasterizer which runs on a separate thread from the view.
+// Calls into this object, including its creation, must be posted to the
+// correct message loop by the view.
+class Rasterizer {
+ public:
+  Rasterizer(mojo::ApplicationConnectorPtr connector,
+             mojo::gfx::composition::ScenePtr scene);
+
+  ~Rasterizer();
+
+  void PublishFrame(std::unique_ptr<Frame> frame);
+
+ private:
+  mojo::GLContextOwner gl_context_owner_;
+  mojo::skia::GaneshContext ganesh_context_;
+  mojo::ui::GaneshRenderer ganesh_renderer_;
+  mojo::gfx::composition::ScenePtr scene_;
+
+  DISALLOW_COPY_AND_ASSIGN(Rasterizer);
+};
+
+}  // namespace examples
+
+#endif  // EXAMPLES_UI_NOODLES_RASTERIZER_H_